Generation of Square Cavity Using Planetary EDM

Abstract

The design and manufacturing of complex shaped 3D features have a wide range of applications in todays manufacturing industries. With machining of hard materials continues to attract much interest in this field, EDM remains an indispensable process to carry out this purpose despite its limitations compared to conventional machining processes in terms of material removal rate and surface quality. Many process improvement techniques have been reported by researchers to overcome these limitations and out of them, incorporation of tool electrode kinematics is observed to have a significant effect. In the present investigation, an attempt has been made to study the effectiveness of two different tool motions in the generation of non-circular cavities. Tool electrode is moved on planetary and diagonal paths during this study. Effects of various electrical and non-electrical parameters on EDM responses have been studied. Current, pulse ON time and voltage are considered as the electrical parameters while tool kinematics parameters like tool path offset and scanning speed have been selected as the non-electrical parameters. Experiments have been carried out the study the effect of tool movement on planetary and diagonal path on different response characteristics viz. Material removal rateand Wear Ratio. It has been observed that planetary motion is a better strategy than diagonal motion for the generation of non-circular cavities in terms of achievement of the response characteristics. The results observed are critically discussed.